Traffic Q&A: When traffic is busy, use both lanes until it’s time to merge

When traveling south, there are two lanes until you reach 154th Street, where the lanes start merging into one.

What’s happening is that most drivers get in the left lane at Military Road, a half-mile before the merge, and then won’t let anybody else in. They go so far as to straddle the line between lanes so you can’t pass on the right.

It seems to me that traffic would move so much more efficiently if the folks in the left lane would just take turns. Also, it seems it would make more sense to be utilizing both lanes as far as possible.

Isn’t it correct to remain in the right lane until you reach the merge sign and then merge? — Eva Jo Robb, Spanaway

Ray Crumbley, an assistant traffic design engineer at the Washington State Department of Transportation, says the relative efficiency depends on the volume of traffic and how it’s flowing.

If traffic is light and free-flowing, traffic moves better if drivers merge early. If traffic is heavy, it’s more efficient if people fill both lanes all the way to the end and then zipper together, politely taking turns.

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